It has long been recognized that the construction of buildings and the like require that many of the basic utilities supplied throughout the building be contained within walls of the building. Such is done for aesthetic purposes as well as for functional reasons. It is imperative for the electrician and the plumber, as well as other tradespeople, to run and mount wires, fixtures, conduits and plumbing through the walls of a building while those walls are still in their rough stages of construction. Once these various wires, fixtures and other items of such utility construction have been mounted and installed, a safety inspection of them can be made. After the safety inspection has cleared the way for covering the walls and sealing their contents, the drywallers can attend to the task of finishing the walls by attaching the drywall panels to the wall studs.
One problem which is inherent to this process is that, with the drywall attached and in place, it is then necessary to uncover electrical fixtures previously mounted within the walls so that the electrical finish work can be accomplished. In the experience of this inventor, conventional measures which are taken to mark the location of such buried electrical fixtures, such as marking the floor at or just below fixture, often result in fixtures being located slightly off from where they actually are mounted. That is, an electrical receptacle box which is thought to exist in one location, when uncovered, often ends up being slightly off from where it was expected to be. Without precise locating of such electrical receptacle boxes, extensive additional drywall work can result where holes or gaps must be patched adjacent the electrical box and, in extreme cases, whole sections of drywall must be extensively repaired.